Apparatus for the blowing of a two-compartment can

ABSTRACT

An apparatus for the blowing of a two-compartment can of the type comprising two compartments, interconnected back-to-back in the area of their walls and facing one another in which there is at least one handle on the top side of the can and one radially inclined spout each on the top side of the compartments. Below an extruder extruding a single tube of hot thermoplastic material and laterally thereto there are provided two blow-mold sections adapted to be moved horizontally toward and away from one another and in closed condition to form the blow mold for the complete can. In each blow-mold section there is a separating wall with interior cooling, the wall corresponding in position and dimension to the slot between the compartments and being spaced in accordance with the thickness of the connecting strip between the compartments. In the plane of junction two inclined spindle sleeves extend in accordance with the bisected apertures for the spouts in the blow-mold sections. The upper portions of the spindle sleeves are, in their position of closest proximity, closer to one another than the inner diameter of the tube and are positioned directly under the lower edge of the tube. The spindle sleeves are adapted to be moved outwardly and upwardly, pulling the extruded tube along, without the thus oppositely placed inner sides of the tube touching one another. The lower edge then extends to a length corresponding to approximately half the circumference of the tube and the upper portions of the spindle sleeves are placed in position for the bisected holes for the spouts and the apparatus in fully closed position of the blowmold sections is then ready for blowing.

uited States ateut 1 Schiemauu [54] APPARATUS FOR THE BLOWING OF ATWO-COMPARTMENT CAN [76] Inventor: Wolfram Schiemann, Eugen-NageleStrasse 17, 714 Ludwigsburg, Germany [22] Filed: Nov. 12, 1971 [21]Appl. No.: 198,298

Primary Examiner-J. Spencer Overholser Assistant Examiner-Michael 0.Sutton AttorneyM. Robert Kestenbaum [57] ABSTRACT An apparatus for theblowing of a two-compartment can of the type comprising twocompartments, inter- 1 Apr.3,i973

connected back-to-back in the area of their walls and facing one anotherin which there is at least one handie on the top side of the can and oneradially inclined spout each on the top side of the compartments. Belowan extruder extruding a single tube of hot thermoplastic material andlaterally thereto there are provided two blow-mold sections adapted tobe moved horizontally toward and away from one another and in closedcondition to form the blow mold for the complete can. In each blow-moldsection there is a separating wall with interior cooling, the wallcorresponding in position and dimension to the slot between thecompartments and being spaced in accordance with the thickness of theconnecting strip between the compartments. In the plane of junction twoinclined spindle sleeves extend in accordance with the bisectedapertures for the spouts in the blow-mold sections. The upper portionsof the spindle sleeves are, in their position of closest proximity,closer to one another than the inner diameter of the tube and arepositioned directly under the lower edge of the tube. The spindlesleeves are adapted to be moved outwardly and upwardly, pulling theextruded tube along, without the thus oppositely placed inner sides ofthe tube touching one another. The lower edge then extends to a lengthcorresponding to approximately half the circumference of the tube andthe upper portions of the spindle sleeves are placed in position for thebisected holes for the spouts and the apparatus in fully closed positionof the blow-mold sections is then ready for blowing.

3 Claims, 6 Drawing Figures PATENTEDAPR3 197s 3.724.987

SHEET 3 BF 3 Ail! m Fig. 5

Fig. 6

APPARATUS FOR THE BLOWING OF A TWO- COMPARTMENT CAN This inventionrelates to an apparatus for the blowing of a two-compartment can,wherein the two compartments being interconnected in back-to-backfashion in the area of their walls facing one another, comprise a handleon the top of the can surface and one spout each on the top surface ofthe compartments, with the spouts extending in radial direction.

It forms part of the art to combine two compartments forming smallindividual cans into a single can. Twocompartment cans are convenientfor the transportation of two different fluids, for example gasoline andlubricating oil for the. preparation of two-stroke mixtures. In cans ofthe known kind, a large-size snap button is moulded on that side on thefirst compartment which faces the second compartment. Said snap buttonis then locked in a corresponding recess in the opposite wall of thesecond compartment. In order to prevent a rotation of the compartmentsabout the horizontal axis of the snap button, a catch and a reinforcingseam are additionally provided on the walls facing one another. Cans ofthis kind require two operational steps in their manufacture and thenassembly by hand. These cans are insufficient as to their durability,capacity and rigidity. The handle can only be provided on one of thecompartments and a shortage of space is encountered when the handle isto be centered on the common point of gravitation of both compartments.Moreover, the handle only reinforces the rigidity of that compartment towhich it is affixed.

It is the object of this invention to disclose an apparatus permittingby means of a single operational step the manufacture of two-compartmentcans of this kind and their permanent interconnection in a simple andpractical fashion with a negligible requirement of material. v

According to this invention, this object is achieved in that below anextruder being adapted to extrude a single tube of hot thermoplasticmaterial and laterally to said tube two blow-mould sections are providedwhich are adapted to be horizontally moved toward and away from oneanother and which in closed position form the blow mould for thecomplete can, in that in each blowmould section a separating wall withinterior cooling is provided which in. its position and dimensioncorresponds to the slot between the two compartments and by its surfacefacing the plane of junction is spaced therefrom in accordance with thethickness of the connecting strip between the compartments, in that inthe extension of the plane of junction two spindle sleeves are providedwhich in accordance with the bisected apertures of the blow-mouldsections being provided for the spouts are inclined in the plane ofjunction, in that the upper portions of the spindle sleeve in theirmutually closest spacing extend in greater mutual proximity than theinner diameter of the tube and are disposed directly below the loweredge of the tube, in

that the spindle sleeves are adapted to be moved upwardly and outwardlyand in the process pull the extruded tube flat without permitting thethus oppositely extending inner surfaces of the tube to touch oneanother, in that the lower edge then extends at a length correspondingto approximately half of the circumference of the tube and the upperareas of the spindle sleeves correspond in their position to thebi-sected apertures for the spouts and in that with thereupon completelyclosed blow-mould sections the apparatus is prepared for blowing.

Further advantages and features of this invention may be gathered fromthe subsequent description of a preferred embodiment, illustrating bythe drawing in FIG. 1 a sideview of a completed can without screw caps,

FIG. 2 a plan view of FIG. 1,

FIG. 3 a schematic side view of the apparatus after extrusion of thetube, however before closure of the blow-mould sections and upward andoutward movement of the spindle sleeves, I

FIG. 4 a view according to FIG. 3, however with closed blow-mouldsections and with the spindle sleeves in their terminal operativepositions,

FIG. 5 a horizontal cross-section of a section of the blow mould,

FIG. 6 one of the sections of a separating wall before fusing to theblow-mould section according to FIG. 5.

Can 11 comprises two compartments 12 and 13, forming substantiallyrectangular flat bodies. Compartment 12 has a capacity of 5 liters,whereas compartment 13 has a capacity of 2% liters. Both compartments12, 13 comprise on their upper surfaces, facing in opposite directions,.inclined portions 14, 16 from which threaded spouts 17 and 18 extend.This permits the filling and emptying of compartments 12 and 13 by meansof their respective spouts 17, 18. In and symmetrically toplane ofjunction 19 is provided a handle 21 extending by means of a first root22 in close proximity to spout 17 into the upper surface of compartment12,

by means of a second root 23 in close proximity to spout 18 into theupper surface of compartment 13 and by means of a third root 24 intocompartment 12 as well as into the upper surface of compartment 13.Compartments l2, 13 are attached to one another along their walls 26, 27by means of a narrow strip 28. Said strip extends at its upper portion29 into handle root 24 and terminates in its lower portion 31 flush withthe lower surface of can 11. Thus there are formed between cans l2, 13two narrow vertical slots 32, 33 which in the present embodiment arespaced 3 4 mm apart and extend to a more than 10-fold depth. These arenarrow, large-surfaced slots 32, 33 extending transverse to plane ofjunction 19.

As revealed by FIG. 1, handle roots 22, 24 are provided with pinch spots34, 36 so that roots 22, 24 are rendered solid and in handle 21intersect the otherwise hollow space 37. A handle of this type thusprevents any fluid from spilling from one compartment into the other.

In accordance with FIGS. 3 and 4, an extruder 38 produces a suspendedcircular hot tube 39 of adequate length. Extruder 38 is conventionallyof the stationary type. Lower edge 41 of tube 39 extends to belowblowmould sections 42, being disposed for movement in horizontal andlinear manner toward one another, transverse to plane of junction 19, i.e., transverse to the drawing plane of FIGS. 3 and 4, until the mould isclosed and away from one another until the mould is opened. Theblow-mould sections are with regard to the plane of junctionsubstantially symmetrical so that it will be sufficient to describe onlyone of them.

Threaded spout 17 is in its lower portion radially inclined and providedwith an open-rimmed bisected opening 43 which is threaded on its innerwall.

Moreover, there is a bisected threaded opening 44 provided for spout 18which is inclined in the opposite direction. FIG. also affords a planview of bisected recesses 46, 47, 48 for handle roots 22, 23, 24.Section 21 of the handle is restricted by means of interrupted line 49.In recess 46, 47 are provided radially extending ribs 51, 52 formingpinch spots 34, 36. In accordance with slot 33 a separating wall 53extends perpendicular to plane of junction 19 across the full height ofblowmould section 42. Corresponding to half of the thickness of strip28,face 54 of separating wall 53 does not fully extend to edge 56.Separating wall 53 is made from two plates, plate 57 of which isschematically illustrated in FIG. 6. The plate has a width correspondingto one-half of that of slot 33. In the inner surface of plate 58 ameander-shaped recess 59 is provided which enters plate 57 at inlet 62and exits at outlet 61. A second mirror-inverted plate is sealinglyconnected to plate 57 so that recesses 59 of both plates permit thepassage of water. Both plates are inserted into blowmould section 42,fused thereto and provided with the required round-offs 63 by means ofapplication of material. In blow-mould section 42 there are waterconnections provided which are flush with inlet 62 and outlet 61,respectively so that separating wall 53 can be cooled from the outside.Such a cooling is essential because it prevents upon opening of theblow-mould sections that separating wall 53 sticks to the lateralsurfaces of slot 33. In spite of this cooling, those portions of 39which correspond to strip 28 can be fused completely and seamlessly.

Below edge 41, two moving means 64, 66 are provided which areschematically illustrated in the form of boxes. These moving means maybe operated by either pneumatic, hydraulic, mechanical or some otherform of power. At any rate, they permit two spindle sleeves 67, 68 beingdisposed in plane 19 to move in a composite movement according to arrows69, 71, 72, 73 upwardly as well as outwardly so that spindle sleeves 67,68 are moved in similar paths in opposite directions and their tipsdescribe arcuate movements according to arrows 74, 76, as shown ininterrupted line. Spindle sleeves 67, 68 engage in their upward andoutward movement the edge of the initially circularly hanging tube 39and move it outwardly, as shown in FIG. 4. Edge 41 is thereby either notat all or only slightly stretched and, as may be seen from substantiallyperpendicular restricting. lines 77, 78, tube 39 is held by spindlesleeves 67, 68 at a sufficient width. Due to the diameter of spindlesleeves 67, 68 the oppositely disposed portions of the inner walls oftube 39 are not in contact with one another as they would otherwisestick together. When blow mould sections 42 are in closed position, theblowing process is started. Blowing is conducted at approximately 10atm. and the two compartments 12, 13 are formed. Spindle sleeves 67, 68form the inner mandrel for threaded spouts 17, 18. Due to the fact thatthe pressure in both compartments 12, 13 is the same, strip 28 isdeflected neither into compartment 12 nor into compartment 13. Minordifferences in pressure have practically no effect as strip 28 is anarrow one. A certain amount of excess pressure in compartment 12 wouldnot push the material in the area of strip 28 into compartment 13,because due to its viscosity and the small space between faces 54 itwould not flow toward compartment 13. The pressure prevailing incompartment 13 also forms the hollow space in handle 21. It would befeasible to pinch all of the handle by means of extending ribs 51, 52 sothat there is no hollow space left.

Upon a cooling period, spindle sleeves 67, 68 are extended in thedirection of threaded spouts 17, 18 while blow-mould sections 42 remainclosed. When blowmould section 42 is opened, the can blank is ejectedand falls out, whereupon spindle sleeves 67, 68 return to theirposition, as illustrated in FIG. 3.

What is claimed is:

1: An apparatus for the blowing of a two-compartment can, wherein thetwo compartments are interconnected back-to-back in the area of theirwalls facing one another, having at least one handle on the top side ofthe can and one radially inclined spout each on the top side of thecompartments comprising two blow-mold sections provided below anextruder extruding a single tube of hot thermoplastic material andlaterally-thereto,

the two blow-mold sections being adapted to be moved horizontallytowards and away from one another and in closed condition to form theblowmold for the complete can,

a separating wall with interior cooling provided in each blow-moldsection, said wall corresponding in position and dimension to the slotbetween the compartments and being spaced in accordance with thethickness of the connecting strip between the compartments,

two spindle sleeves provided at an inclination in the junction plane ofthe blow-mold sections, extending in accordance with the bisectedapertures for the spouts in the blow-mold sections, the upper portionsof the spindle sleeves in their position of closest proximity beingcloser to one another than the inner diameter of the hot thermoplasticmateria] extruded tube and positioned directly under the lower edge ofthe extruded tube of hot plastic material,

means for moving the spindle sleeves outwardly and upwardly, therebypulling the extruded tube along, without the thus oppositely placed.inner sides of the extruded tube touching one another,

the lower edge of the extruded tube extending to a length correspondingto approximately half the circumference thereof,

the upper portions of the spindle sleeves being adapted to be placed inposition for the bisected holes for the spouts, the apparatus in fullyclosed position of the blow-mold sections then being ready for blowing.

2. An apparatus according to claim 1, in which bisected recesses areprovided in the blow-mold sections for a centered handle which extendfrom the recess in one compartment to the recess in the othercompartment and in the area of at least one of the handle roots a rib isprovided in the bisected recess, the cross-section of which displacesthe interior space of the centered handle and renders the root solid.

3. An apparatus according to claim 2, in which the bisected recesses forthe handle roots are provided on both sides of the separating wall.

1. An apparatus for the blowing of a two-compartment can, wherein thetwo compartments are interconnected back-to-back in the area of theirwalls facing one another, having at least one handle on the top side ofthe can and one radially inclined spout each on the top side of thecompartments comprising two blow-mold sections provided below anextruder extruding a single tube of hot thermoplastic material andlaterally thereto, the two blow-mold sections being adapted to be movedhorizontally towards and away from one another and in closed conditionto form the blow-mold for the complete can, a separating wall withinterior cooling provided in each blowmold section, said wallcorresponding in position and dimension to the slot between thecompartments and being spaced in accordance with the thickness of theconnecting strip between the compartments, two spindle sleeves providedat an inclination in the junction plane of the blow-mold sections,extending in accordance with the bisected apertures for the spouts inthe blow-mold sections, the upper portions of the spindle sleeves intheir position of closest proximity being closer to one another than theinner diameter of the hot thermoplastic material extruded tube andpositioned directly under the lower edge of the extruded tube of hotplastic material, means for moving the spindle sleeves outwardly andupwardly, thereby pulling the extruded tube along, without the thusoppositely placed inner sides of the extruded tube touching one another,the lower edge of the extruded tube extending to a length correspondingto approximately half the circumference thereof, the upper portions ofthe spindle sleeves being adapted to be placed in position for thebisected holes for the spouts, the apparatus in fully closed position ofthe blow-mold sections then being ready for blowing.
 2. An apparatusaccording to claim 1, in which bisected recesses are provided in theblow-mold sections for a centered handle which extend from the recess inone compartment to the recess in the other compartment and in the areaof at least one of the handle roots a rib is provided in the bisectedrecess, the cross-section of which displaces the interior space of thecentered handle and renders the root solid.
 3. An apparatus according toclaim 2, in which the bisected recesses for the handle roots areprovided on both sides of the separating wall.